Novel interventions for recalcitrant patella tendinopathy: Results may favour autologous blood injection (ABI) over radial-extra-corporeal shockwave therapy (r-ESWT) - A prospective cohort study

Abstract

Background: Patella tendinopathy is a common condition in a number of sports and can have a significant impact on activity and quality of life. Whilst rehabilitation leads to improvements in the majority of cases, a number of adjunct treatments are available for resistant cases with limited evidence supporting the use of one treatment over another.Hypothesis/Purpose: To compare the outcomes for patients with chronic patella tendinopathy, following either radial-Extra-Corporeal Shockwave Therapy (r-ESWT) or Autologous Blood Injection (ABI). Study design: Prospective cohort study. Methods: 28 consecutive patients with chronic patella tendinopathy, treated with radial-ESWT (n = 14) or ABI (n = 14), with minimum three-month follow-up. Mean age 34.2 years, mean duration of symptoms 32.8 months. Patients received either three sessions of radial-Extra-Corporeal Shockwave Therapy (one session per week for 3 weeks), or two ultrasound-guided Autologous Blood Injections (2 injections performed 2-4 weeks apart). All patients received standardised after-care, including continuation of a structured home exercise programme of flexibility and progressive loading (eccentric strengthening) exercises. Main Outcome Measures were Victoria Institute of Sport - Patella questionnaire (VISA-P), plus 0-10 Visual Analogue Scale (VAS) for self-reported levels of "average pain". Results: There were statistically significant improvements in self-reported measures of pain/function following either procedure at 6-weeks and at 3-months, but only in the ABI group at 6-months. At 3-months: VISA-P was improved from 32.4% ± 11.7%-60.0% ± 20.7% (p < 0.01) in the ABI group, and from 34.2% ± 14.6%-48.9% ± 17.8% (p < 0.001) in the r-ESWT group. Conclusions: Patients with chronic patella tendinopathy improved at 6-weeks and 3-months following either ABI or r-ESWT procedure, with significant benefits at 6-months seen only in the ABI group. Between group analysis demonstrated improved outcomes favouring ABI compared to r-ESWT at the 6-month timepoint using VISA-P, and at all time-points using VAS as outcome measures. The small sample sizes in this pragmatic study are however noted, which limit interpretation, and larger more robust studies are required to investigate this further. This pragmatic prospective cohort study demonstrates improvements following either r-ESWT or ABI procedures, with results potentially favouring ABI over r-ESWT for patients with chronic patella tendinopathy.